The Circuit Court has ruled that PLS must reduce dioxane levels to less than 85 ppb west of Wagner Road (to the extent possible)... and keep dioxane levels less than 2800 ppb east of Maple Road. The 85 ppb is Michigan's residential groundwater cleanup standard for dioxane, and the 2800 ppb is the groundwater/surface water standard where surface water is not used for drinking.
The problem is that between Wagner and Maple road, there is a huge amount of dioxane ... too much to let go at 2800 ppb without knowing where it will eventually end up. Recent findings seem to indicate that the plumes may flow outside the current Prohibition Zone. Some dioxane may flow more northerly that predicted, some may go under the river, and some may turn and follow along the river. In each of these cases, some water supply wells may become contaminated at some point in the future.
supports the position that more aggressive cleanup be done between
Wagner and Maple roads as well as at the Core and Evergreen plumes where
access points exist... before the large mass of dioxane gets to areas
where it is harder to clean up.